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Climate change is producing large impacts on rivers, amplifying hydrological extremes. Prolonged drought periods result in dramatic stress for river biota and associated processes due to low discharge, reducing the interactions between rivers and their lateral environments or leading to hydrological intermittency. New quantitative methods are needed, to correlate discharge with the available riverine habitats. In this work we have mapped the wet surface and paths of two stretches of the Taro and Trebbia Apennine rivers, analyzing satellite images from periods with contrasting discharge. The considered stretches are critical due to different human pressures (large water withdrawals for agriculture and industrial use) and are particularly vulnerable to further, climate‐driven discharge reductions. The produced images offer multiple possibilities to extract qualitative and quantitative information at the whole stretch scales, including habitat reduction along with decreasing discharge, threshold discharge limiting lateral interactions, or the evaluation of longitudinal river continuity. We discuss the limitation and the potentialities of the method and the maps produced in terms of possible application in the field of river geomorphology, ecology, the definition of ecological river flow, risk assessment, and river management. [ABSTRACT FROM AUTHOR]

This paper investigates the role played by geomorphological and tectonic processes affecting a portion of an active mountain belt in causing the occurrence of different types of landslides developed in flysch bedrock. The adopted multidisciplinary approach (geomorphology, geology and geophysics) allowed to recognize in a portion of the Northern Apennines of Italy different types of landslides that developed in response to slope dynamics, in turn dependent on broader regional-scale tectonic processes. Sedimentary bed attitude, local tectonic discontinuities and lithology only partially influenced the type of landslides, which have been deeply affected by the activity of regional-scale antiform that controlled the hillslope geomorphic evolution in different ways. The growth of this structure and the tilting of its forelimb produced gently dipping slopes that approached the threshold angle that can cause the occurrence of (mainly) translational rockslides. Conversely, high-angle normal faulting parallel to the antiform axis (related to a later stage of activity of the antiform itself) strongly controlled the stream network evolution and caused the watercourses to deeply incise portions of their valleys. This incision produced younger steep valley slopes and caused the development of complex landslides (roto-translational slides-earth/debris flow). The results of the integrated study presented in this paper allowed to distinguish two main types of landslides whose development reflects the events that led to the geomorphological and geological evolution of the area. In this perspective, within the study area, landslides can be regarded and used as indicators of broader-scale recent tectonic processes. [ABSTRACT FROM AUTHOR]

New sedimentological sea-level indicators are presented from the River Magra coastal plain, in NW Italy. Chronologically well-constrained paralic peats and organic sediments which had been deposited in a defined relationship with sea level were recovered in four of the seven boreholes considered in this work. Their evolution scatters in the time span of the past 6000 years. Since the cores are located within a single sedimentary basin, it was possible to correct the elevation of marker horizons for the effect of sediment compaction by means of both a field and a geotechnical method. Thus, seven reliable index points for the mid- to late-Holocene sea-level rise were obtained. The age-depth model derived from them was compared with that of sea-level predictions from two different Glacial Isostatic Adjustment (GIA) models available for the area. In both cases, the modelled sea-level estimates overlie the index points, suggesting lower relative sea-level elevation than the one predicted considering the combined eustatic and hydro-isostatic components. Based on the general tectonic setting of the area, this finding was interpreted as the effect of a tectonic subsidence of the basin, the rate of which can be quantified on average as 0.5 mm/yr since the middle Holocene, with a sharp increase after 2500 yr BP. By providing a reliable estimate of the rate of tectonic subsidence in a coastal area of NW Italy, this research contributes to refining the geodynamic model of this part of the Mediterranean basin. [ABSTRACT FROM AUTHOR]

The main aim of this study is the experimental analysis of the hydrogeological behaviour of the Mt. Prinzera ultramafic massif in the northern Apennines, Italy. The analysed multidisciplinary database has been acquired through (a) geologic and structural survey; (b) geomorphologic survey; (c) hydrogeological monitoring; (d) physico-chemical analyses; and (e) isotopic analyses. The ultramafic medium is made of several lithological units, tectonically overlapped. Between them, a low-permeability, discontinuous unit has been identified. This unit behaves as an aquitard and causes a perched groundwater to temporary flow within the upper medium, close to the surface. This perched groundwater flows out along several structurally controlled depressions, and then several high-altitude temporary springs can be observed during recharge, together with several perennial basal (i.e., low altitude) springs, caused by the compartmentalisation of the system because of high-angle tectonic discontinuities. [ABSTRACT FROM AUTHOR]

This paper presents a geomorphologic map of the Mt. Prinzera ultramafic rock complex (Parma Province, Emilia-Romagna Region, Italy) mapped at large scale (1:2500). The map is the first contribution to the detailed geomorphologic knowledge of the area within the framework of a multidisciplinary approach used to analyse Mt. Prinzera as a hard rock aquifer case study. The geomorphologic mapping was carried out by field survey and aerial photograph analysis. All the surface processes and landforms were considered, with particular attention to structural geomorphologic features. The mapping of linear morphologic features was considered useful for revealing the presence of sets of joints otherwise difficult to detect due to surface weathering. Sets of rock discontinuities are important for water seepage and percolation and their identification is crucial for developing the hydrogeological conceptual model of the aquifer. [ABSTRACT FROM PUBLISHER]